The invention concerns a mechanical actuating device for hydraulic control valves having complex control functions, which can be assembled from modular units, each of them having control valve bodies operated by longitudinal displacement in a housing that can be joined to the housing of the adjacent module, and by means of which passages to adjacent modules and/or external circuits are opened or closed according to the position in which they are set, the operation of the valve bodies being accomplished by mechanical action on the ends of the valve bodies which protrude from the module housings on the same side of the latter.
Control valves for hydraulic systems can have very complex functions depending on the connections which are to be established simultaneously as required in a particular operation. It can be understood that such control valves require complex valve bodies (slide valves bodies for example) and valve housings, so that the manufacturing costs for control valves of only two functions is increased all out of proportion to those of only one function. Now, it is fundamentally also possible to provide for complex control functions by an appropriate combination of single-function valves, and in practice this is often done. In order in such cases to achieve compactness the housings of the unit valves are fastened together in part directly, i.e., without the interposition of conduits, to form modular assemblies, in which case passages provided in the confronting housing surfaces provide a direct communication between the assembled valves. In order to assure the proper operation of hydraulic systems using such ganged valves, the valve bodies of the individual valves must be operated in synchronism. This is basically possible by simultaneous hydraulic operation or electromagnetic actuation, in which case, however, the hydraulic systems are additionally complicated by the required hydraulic or electromagnetic actuating systems.